PCI: hotplug: pciehp: wait for 1 second after power off slot

According to the specification, we must wait for at least 1 second
after turning power off before taking any action that relies on power
having been removed from the slot/adapter.

Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Kristen Carlson Accardi <kristen.c.accardi@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/pci/hotplug/pciehp_ctrl.c

@@ -197,6 +197,12 @@ static void set_slot_off(struct controller *ctrl, struct slot * pslot)
 			    __FUNCTION__);
 			return;
 		}
+		/*
+		 * After turning power off, we must wait for at least
+		 * 1 second before taking any action that relies on
+		 * power having been removed from the slot/adapter.
+		 */
+		msleep(1000);
 	}
 }
 
@@ -615,6 +621,12 @@ int pciehp_disable_slot(struct slot *p_slot)
 			mutex_unlock(&p_slot->ctrl->crit_sect);
 			return -EINVAL;
 		}
+		/*
+		 * After turning power off, we must wait for at least
+		 * 1 second before taking any action that relies on
+		 * power having been removed from the slot/adapter.
+		 */
+		msleep(1000);
 	}
 
 	ret = remove_board(p_slot);